The Future of Extreme Cold in a Warming World

Jan 24, 2018

By Climate Central

For much of the U.S. east of the Rockies, middle to late January tends to be the coldest time of the year. Even though extreme cold can still happen in winter, as was seen earlier this year in much of the country, the frequency and intensity of extreme cold is declining as the world warms from the increase in greenhouse gases. Digging deeper, this week’s analysis examines the coldest night each year in cities across the country, and in most cases, the trend in that coldest night is warmer.

Trends in extreme cold for these U.S. cities

With no change in the rate of greenhouse gas emissions, warming of the lowest temperature of the year will continue. According to the 2017 U.S. Climate Science Special Report, that coldest reading each year will rise several degrees in parts of the U.S. by the middle of this century. The warming will be most prevalent in the Upper Midwest, across the Great Lakes, and in the Northeast, where up to 10°F of warming is projected.

While the decrease in cold may sound good on a cold winter day, that warming comes with consequences for farming, recreation, economy, and the environment. Fruit trees, which need to become dormant over the winter to bloom in the spring, may produce smaller yields. Winter-based activities in colder climates, like skiing and snowmobiling will become less prevalent, and the tourist economies that support them may struggle. More disease-carrying insects, like ticks and mosquitoes will survive through a milder winter.

Methodology: Minimum temperature data for individual sites is analyzed through 2017. Projections are from the 2017 U.S. Climate Science Special Report. Changes in minimum temperature extremes reflect the difference between the average for mid-century (2036-65) and near present (1976-2005) under the RCP8.5 emissions scenario, and are derived from 32 downscaled climate models. Former Weather Channel meteorologist Guy Walton maintains a comprehensive records database, analyzing monthly, annual, and decadal records trends based on NCEI data.

As the world warms, the overall area of North America covered by snow is decreasing. One reason is because an increasing percentage of winter precipitation is falling as rain instead of snow in many locations. A Climate Central report found that between sea level and 5,000 feet in elevation across the Western U.S., a smaller percentage of winter

Winters are warming across the U.S., and in some locations, the warming is dramatic. The Northern Plains, Great Lakes, and the Northeast are warming the fastest, while warming is taking place at a slower rate in the western U.S. In parts of Minnesota, Wisconsin, and northern New England winters have warmed at an average rate of more than 1°F per

Coming off of a warm September, warmer falls are becoming a trend across the U.S., with the first freeze (temperature below 32°F) of the season arriving later than before. This trend is not limited to one area of the country. The first freeze is coming a full month (31 days) later in Boise, Idaho, 27 days later in Las Vegas, Nevada, and 24 days lat